Background: Combination therapy with an alpha-glucosidase inhibitor or glinide plus a dipeptidyl peptidase-4 inhibitor is thought to be effective for glycemic control because of its effects on postprandial hyperglycemia. However, no studies have directly compared these two combination therapies in relation to efficacy and safety.
Methods: Eighteen patients with type 2 diabetes were studied. All had diabetes not adequately controlled with diet and exercise therapy, an HbA1c level of ≥7.5%, and were not receiving any medication for diabetes. The patients were randomized to either miglitol- or repaglinide-based combination therapy with alogliptin. Patients received miglitol or repaglinide monotherapy for 3 months (the miglitol and repaglinide groups, respectively), after which alogliptin was added to each group as combination therapy for 3 months. A meal tolerance test (MTT) was performed before the start of treatment and at the end of monotherapy and combination therapy.
Results: During the study period, decreases in HbA1c and glycated albumin were significantly greater in the repaglinide group than in the miglitol group; however, there was no significant difference between treatment groups at the end of the study. At the end of monotherapy, insulin secretion relative to glucose elevation (ISG0-30: area under the curve of insulin from 0 to 30 min during MTT [AUC0-30 of IRI]/AUC0-30 of plasma glucose) was significantly higher only in the repaglinide group; ISG0-30 did not significantly increase in either group after the addition of alogliptin.
Conclusions: The addition of alogliptin to repaglinide monotherapy did not cause glucose-independent inappropriate insulin secretion and did not appear to increase the incidence of hypoglycemia.
Keywords: alogliptin; miglitol; postprandial hyperglycemia; repaglinide.